Question

The total weight of three girls is 95 kg. If two of them weigh 27kg 325g and 32 kg 775g respectively. What is the weight of the third girl?

Answer 1

Hint: Start by letting the weight of the girl with unknown weight to be x. Then convert all the weights to a single unit and use the total weight to form the equation.

Complete step-by-step answer:

To start with the solution, we let the weight of the unknown girl be x kg.

Now converting all the weights to suitable units using the data that 1kg is equal to 1000g. We will convert all the weights to kilograms as the total weight is also given in kilograms.

So, the weight of the first girl=27kg 325 grams= $\left( 27+\dfrac{325}{1000} \right)kg=27.325kg$

Similarly, the weight of the second girl=32kg 775 grams= $\left( 32+\dfrac{775}{1000} \right)kg=32.775kg$

Now, as given in the question, the weight of all three girls is equal to 95kg. This can be mathematically represented as:

Weight of first girl + weight of second girl + weight of third girl = 95 kg

$\Rightarrow $ 27.325 + 32.775 + x = 95

$\Rightarrow $ x = 95-60.1

$\Rightarrow $ x = 34.9kg

Therefore, we can conclude that the weight of the third girl is equal to 34.9kg, which can also be written as 34kg 900g.


Note: Don’t get confused by the term weight in the question. According to definitions in physics, weight is mass multiplied by the gravitational force, but in mathematics, mass and weight mostly refer to the same thing and expressed in kilograms or grams.